SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1745e071bf355c6f5f6c810afab6230b4ff51fa2cd219b5dc091c3995935feea' 
  AND token = '630FJfffpD9Kh3TRSdxE6rvBwTtopsQAU8UMG11+XSw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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