SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c30df674158aa7cc09c3c6a3875f91738284f5f916d58ae4ae274df2e066b48a' 
  AND token = 'fZBIYba30yCin0y5/KpJsY5b8gfojuuJrKXmDOxqHBo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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