SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '074bd0681738dce680b9e314ee9acd7384a7b62dc0ce37dc09d0deacce5a65bd' 
  AND token = 'kpTl9NJr2GqMuYMjjZOThiOFzIdxrLuLpuIXyRRcNlY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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