SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6cb8a2fafde1a417b01626f23c96a38695937e98c810a26ef4faec464bfe8b6c' 
  AND token = 'y9uaBR+Lqknm2hA9gvFQGhhhD7Ew72DwAZ7EzLawlcU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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