SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e03fe4f19e746c0898ccdc509aae4bd5e4cfd1a4de75d520ce7095e6226afaf9' 
  AND token = 'wouUi0vbGojgBQ9vc+NhSpC5XV1hAMdcud8Z0QrVW5s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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