SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a27b2c94d56370c6bcc0e6500df9cdd18ec281c9376076ffd0db8299184847f' 
  AND token = 'l6QxYLw3J0jfq2tZUTgtkDR+Lq1TrfIhXLeUF30E908=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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