SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ff9a60bf6e85e0cd984c0a3364d828f0c224274a7928eab71da70af89b39e37' 
  AND token = 'Zb9w5e6yyumGPTSEpSVNrTWr8SQsJgh8Q+UbPElSNjw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}