SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64f7df50397e6c30bf12e934526fe085a60c14689e5b772157eb323cbe6388d5' 
  AND token = 'CqXPzKWLh+MsmAJXfqQcN8n/j8K18k+9zyN6sWiU7VM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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