SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c31baf9750b4adbeba01fe86af448ff09b3deba3957f1d06ca7d632f1a1879b' 
  AND token = 'CJ00oSwCuHVAcAtUo6Hj6WbO0w9NkFrSzl7NcPQx5pE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

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