SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee2f20c374e4c68159fd4e1719459b69fe91c39af7d0184eb69fbea657979c9a' 
  AND token = 'LVLFX2UXnStXiwWOwk4b25VMLKduRdM14G7TxsNvtgo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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