SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'df873e8cf70e9cbec88bad3d62dda3e12785034a275d8b5faf9dd618c28a2e8d' 
  AND token = 'zQny5Rk+pgR6y+FjEjEePylL9k6ibY04tfxdF+90tqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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