SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '827454a53a1169e338cf627cd13c1561a2bb36442201d4c117c04c476a31dbe7' 
  AND token = 'OA7heYvu+fPsjgorymiUfZPQPlf1FQwNm1zADY2onu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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