SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7a85d92c7c7015a578ec93e5a0090ba0c7d44a0c0a4965d5eba864fc86f914d4' 
  AND token = 'K6a9d8isdbUj+sTVDIrwAX1kUzXOJ2iM3sVxmA5gUQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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