SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c4cdc1f0170e497b27bfe64e9619f132752f710e0972306d28d582ab450befb6' 
  AND token = 'mf6hIB0g4++1KR/2ZoHOO5PsL8WUWzJ4BUuRHwZ+wHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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