SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '50d8798b72f18167c172720d09aaf24abb1cb6e9651766377c59b6bcee78e579' 
  AND token = 'wpDgxNZ2tYAI2d0YE+Eh73QGEOCo5PawxayGPsB0a7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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