SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '514e528b6b402f0770544af470a8ba41f0785c6b22313e2ed9fd7a88a881cdfa' 
  AND token = 'KlUu6HWZtxXwWOnFvqV3gqtb0zNtYayFH2mR6C78JOc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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