SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5944e374915dbebf7e1e74dfb7ba7195cba8dc9f6aaa53b69ecf9fd90972144f' 
  AND token = 'hlHRx/HfR7ixWC7RxHOP0YQROJJBDxYdwx0JAC0ThZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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