SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '901227dc97f662978f6dce80f8f183bb916a5c8107f553d745ee8787389d4fec' 
  AND token = 'glgL0X8QMTQamV2/HEUvrH5v1eVKNhzOqCJ2S9/3rR4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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