SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '93c40b2da1dfa0950779c3e4b1e74640b298db5ca48369c7e41b503ebe75d913' 
  AND token = 'cSqwmhMOzu7cQbfOUOxtTkOuwho0cBNvIzuhhKzJF8U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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