SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce135227ea5cd44f1a180edae8dc7bd3ac6aecf9a9f3ee894404015e0d598c1a' 
  AND token = '0IeSuyy85AukQf7DkBwrJOoz8mfPMGk/zK2vrkOf5GM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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