SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a33772d80d6fabe3245fad36f03fcf7b5cce3c1c59876c9442b6309d63e5911' 
  AND token = 'HydF3Ml+zWDjVFJLEVsdVQtjoQ5CBNJsXHw/ZiltOGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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