SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c204862edd1fc89b10d176582d3b8a86775423dbac4239e36cb0748c75d90105' 
  AND token = 'QXtGCGhWluAadIWFzwL9IKnYFvl4HrvjYWEDwNSvbSo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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