SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '026c1440fa0f7bf1e69d9040e3d231f3916c15d0f165b7a9da0b195de836a6fb' 
  AND token = 'GyRZjEiH9QDDRHXDwSqQI5c2BUHrUn237qsIDi3JXng=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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