SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4abb003852361616dda59f54df029f388b8625fabbaaecd6d026a55a944bd9f' 
  AND token = 'gwejPrQJRVJYYz2W6k76pOZ5J2QVF3spIkrOzcazR1g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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