SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '424c011f7c3000f740b434257cc0cf877f128375a7b3402e6c2eeed453ffe621' 
  AND token = 'APEXoUu7MNcwgEuXdk5WlhLiHXKgZihKyEf/xsYzGNI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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