SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06e9b245be58dfb170c8e308474021dde132950e06841fc5e4a94177ce7db22e' 
  AND token = '4nrrmcXxKuN2w8BCUdkllStCXRL/59Oc/OzXSFCxddg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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