SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '183ae5296a7cdd9052d860203817a5793383752f2d69e40c170c276625da0d00' 
  AND token = 'bYAjQQqssBKXejXmWQiTCxV6Q9kiGtTj0udu+n2FBWg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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