SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9a6cc01eacf117307a4a2fde8a97af292c1ec2981ff2277ba3e277dce96ffef' 
  AND token = 'YwqEALQjwM7iIKOnudU8hHunH5IueQph8yMgiNhjwyc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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