SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f53fab404fc77af1293baa52e40bb8f5cba91d7b58d46be1272cf222e1ec2798' 
  AND token = 'TuR+VwXsqfzBX4OWLvAyMYKVrT9oI2UhJvSvOX4l+wM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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