SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2850075e0cddc44146ba485af658a0773bdfa21b577db3f3c3c58605cb73ce07' 
  AND token = 'PwFlzkcjzBdGJWCQulx2EJ4LcnC0LhKZ+g7VeGfJGT4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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