SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e407eeb83ee78ae816685e069abfec60fa0f09817d3d7d4c65b75d460b003dc0' 
  AND token = 'Tchzw/2dR9TDmW3U+rULIqObZo/PoyDgCVOrbnp2AHk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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