SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4611bbaba0df79c417db6fcf599c6961bd06880d62b4e7e78012e707f4cce700' 
  AND token = 'xFMf/gw/d/r96bDB5fCojVvFpHCjH7HMxgQdGWjdALI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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