SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '08bc5e03d352640f87491f0f418efe050b716b0a4afc07796b5e4199bd3314c5' 
  AND token = '14kFpQFemXheIcb+2mzCYLq/CbmdVTvd7ja64TvjAQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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