SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4f6ef8d1430713f7c3ad00b5e6b8e0adc6adf6695c55203ac45007cf6102993' 
  AND token = 'mrBnixHlMGv5IO963s3bbENanAriXprXrSFJ15zDXvQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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