SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93d7a100b9652ce896f6f13fef9ec74ba0a1651abf188adc8e014247001cfe93' 
  AND token = 'U5bu8PXfMWFO8fViJEYOswuuix482O7yEHsFy35d+hM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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