SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8e5d2554a9ab51582b4e02ab2a67aaed6cb913558ffe8858a6d73d2c74b06cfa' 
  AND token = 'CubaLzynwOSk5rJupZb2Xz+5jdC5jTrBFuDRk0owjVI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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