SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '925058b4ac781145ea827107003e63741f425b68c621c92ea64811e634c4456c' 
  AND token = 'fQiVjD03x+IJZaQDnPrvZ9AqCjkNMfcrdOXoGARblnw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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