SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3459880f6a8059a7d94c9c9fc8f3867ccedbb68fe6acb2b5856b9bd3feae175' 
  AND token = 'ztETeqQ2c5WduGMcAGkQClawCPrBkP1L3Nr/ddKoMew=' 
  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"
    }
  }
}