SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e8627763ee1829b5df5199e364c445b4fe2bdafb26380bf956baea8cd1e84d0' 
  AND token = 'pELv3fCgSEz2MFCzwfogbXMVVNr3CTw82p4SXJ9CfAI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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