SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77f262731b3ee818871b572cddcbbbe374b738c9b96ec7d87bae5dc10712e9ef' 
  AND token = 'BeORxMuJYc+RaqFhAxMwek29fFTRdiIiVuwtdn5bs2g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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