SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '6c96224153fa0ddee0836e4841da6295ba479d5d2cfe4d428128a8758523ce2c' 
  AND token = 'u4IjsUFvdEJ9jUQM0sXnRmIyaDLf89o3lCjFhUY9LHo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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