SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '006885b3841a4c175deff3cac8bfdc73d2b1ace9ffc20ff1426e37670fd34c8c' 
  AND token = '7QhNB6DIHTmAyoPDqZP5QOwCjYu/2lCpiZvQlmSF0y0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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