SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ecb7051fc25edb3d008dcb553ecb61f3616b479c0dd70bfa32eb27d95a989ff' 
  AND token = 'WUekoTvSVcViRQBjfypUbBA5+4oE/nJIQ90RSTEFGYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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