SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '50f6a1a0e17e74a7dab09909cdc762c19c83cdd8d6a751c8e5f75e775889ab0c' 
  AND token = 'rYZstEI/vJCPjHYYIPg7OrX5pzw+cDBjiF9yS+nh2KQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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