SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3fa196ba23a1e8855598d1e25cbd6f90747f62a7db39de26016ffc7e6cb32414' 
  AND token = 'e2I/mBlK8ME2g/9Ow8q85SME1Jz8CM6IECMLskLRYCs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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