SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0eccfb3f0a0037c21f753ec86c3e1e59d727ceefe06a143265e7b5f09463f916' 
  AND token = 'AAlslvOxUQhuymWtbiHKbfAcz5A3sWMNXgaaNDk1Hic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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