SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80fb2f3e9a8cc592ecfdf45d8bd5ce50c28d4dd6ff6e928fb925763c31c3b0d7' 
  AND token = 'yjpO8Og85Ck0iPsKTelLB+TIYNfaWFAPW/2Ez9ATpM0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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