SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05d9c84542f1c55cfdf9805bf18cbb0e48e1a56e9150295b211f367bb691a437' 
  AND token = 'g3QVhvqoUG4CUkgRxG/jIM+lqakvkRGEJrori6832Tc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}