SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'edff14fc31c396c406ad3628627b60e28e3b78b443307c2419fbc4fa5e6de67e' 
  AND token = 'LoDwYVA+mTPOFS68d/g1JXvVbr/Tscx5MYo5aRRBRIU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}