SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '79553771f48178461948c15c7dc8d177d9cf449fe735eeaf4bfa400f46568139' 
  AND token = 'v9IHX7t8muPnj6DB2utFdmg/Op2G9ckZFWYeQtSsg1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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