SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abd82778f5c714269f1c760a4c8bcca7914349ce6cf12d08e04b3e6cc9c45961' 
  AND token = 'MkhYjF+YIu4QjORGsq/s1rCEMgXMy5Tj3Az/o2B7N+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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