SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04aab72b022f5928f069f38cfabf5a8e3477a31022403b96708eaa93fbb78103' 
  AND token = 'vbQkjBpCsqzNbxV/GcI5ohIADjxHamwSyhzYExOrMYM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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