SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '832fbf91e686ac3f1dd810efa8722898ddb6299d80f651d22d9cfd5b0fd885a2' 
  AND token = 'HXvVtwtBjNt+zz9bb7G/WBSVBJ+cAFGSqsNGVdpy7So=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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