SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d3102cf061f6004e2053d7094f0814d4d77c97ab5ad41c2fb8ebd7037132d07' 
  AND token = 'ufPVZmP5q25uLw8Sfubxx1JBQ3U+pjKh9ESVPvArLYA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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