SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6872250a497d160f18b43d0c690d473b3834badd01611fdc98e6e2643e134f5d' 
  AND token = 'KqEBMVkDL8951UppLFwxkWACoKqYeOPfeudOD6Y1fek=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}