SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aaf2b13c723a991e8a1e5ed53144acc3542376a66b9f05723499797a4ef52a21' 
  AND token = '7CdVyjfKmRdxNqqb+CclL7wuvm2VLPWd2wvxmbkVcLk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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