SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee4c26d305f4fc2c8581b3e98d73a4645d27bcf68c95ae12e7679e5e8ba8096b' 
  AND token = 'mW+ngJfDkvpRKGmSCJkqNupULbd1yMijQBn2lk4AIBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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