SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da54aea9e6118ebc53140474b1fc464b9e95e8c302f49227eebde1fc3f2ffa6b' 
  AND token = 'O0POOHCNcCwulkdsFSeJSSi3umW6HGXIEQiPSVaLnF8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00059

JSON explain

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