SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b02141b552fdb8c71a50ff424634fc82d3166f6e2b33635459f4d99d02e8d2f7' 
  AND token = 'hMf3d+m9Pw1NTcNzAkE37BEwuM2qZZ5HLRWcxtr/NS0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00062

JSON explain

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