SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '16ec16c5b10279f35d0a0cdfd3d97e2b02278805196635ae56b8aa8480a9f0c3' 
  AND token = 'aysFj5tjXTsc5XXtYQD1Lt9RCiU/v/G0Hs7KDGmbxmA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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