SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d707b4fc0ba2dcdc3fddf8e38d06f15d1d9693337550d03bd8f68aee316ecd6' 
  AND token = 'hSw1/8YB495oBX74NnceF6QZ2wjiKJyL1/fTBttvdMU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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