SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05c5ea9643228fe8f8dd77346d61544278a1dc04f6b4cc516ee539d94d1dec3b' 
  AND token = 'WBmdx29MaH/ohzedHhZx4ijkVFJkS0Q+qOz+pdL+/+w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}