SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4e8938d97d2460b347bedb66a138cf793fe93271e73ede18d34f104f7d90cd45' 
  AND token = '+2N6OHBbJD0O2hpWMf7xuI8+BIDhn6THRXJvzDQ74XY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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