SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b9ec770123d7170ff7b23a1d622b968c2362917e06d48b028f68486e95e9587' 
  AND token = 'rMtHpT24RUdlDNC0EhC4Y5g8TUfEETerWMXicM7HGNo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}